Coordinated Control Strategy of Scalable Superconducting Magnetic Energy Storage

Superconducting magnetic energy storage (SMES) has the characteristics of high power density and zero impedance that helps to develop renewable energy generation and micro-grid. A coordinated control for large capacity SMES application is proposed in this paper, which can improve power quality and system robustness effectively. Based on the topology and mathematical model of large capacity SMES, the coordinated control of outer power and inner current double closed loops control for power conditioning system is desired and vector switching automatic current sharing control method for multiphase chopper is developed. A low-pass filter and repetitive controller are included in the inner current loop controller to suppress periodic disturbance and increase robustness of the system. Simulation based on MATLAB/Simulink and experimental results demonstrate the effectiveness of large-capacity SMES coordinated control.